Cam.



No. 740,816. PATENTED OCT. e, 1903 W. H. DAILY CAM.

APPLIGATIOH' FILED JAN 12, 1903.

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WITNESSE pm YEA/TOR W 7 By Hs ,7 ATTORNEYS.

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UNITED STATES Patented October c, 190 3.

PATENT OFFICE.

' GAM SPECIFICATION forming part of Letters Patent No. 740,816, dated October 6, 1903.

Application filed January 12, 1903. erial No. 138,699. (No modehl To all whom, it may concern.-

Be it known that 1, WILLIAM H. DAILY, a citizen of the United States, and a resident of Carthage, in the county of Hancock and State of Illinois, have invented new and useful Improvements in Cams, of which the following is a full, clear, and exact description.

This invention relates to improvements in cams, and has particular application in the construction of a device of this character, which is especially adapted for assisting in compressing a gas, a spring, or the like.

In carrying out the present invention I have particularly in view as an object the construction of a cam disk or wheel which shall take its load at a point farthest from the center or at the greatest point of leverage and shall release such spring at a point nearest the center or at the shortest point of leverage. By this means it is possible to compress a spring or a gas without the loss of any power save friction and with the least possible jar to the machinery and the operator.

A further object of the invention is to so construct or form the cam that it shall be compact, simple, easily made, and it shall be.

especially adapted for use on rock-drills, aircompressors, hay presses, baling presses, stamp-mills, and like mechanisms.

In the camsheretofore constructed for use on mechanisms of this character, especially that of hand-powerrock-drills, which are operated by spring-power, it has been customary to take the weight or spring to be compressed at the point nearest to the center of the cam and release it farthest therefrom, this resultin gin the loss of half the power. Forinstance, in the compression of a spring or gas it is readily seen that the more the spring or gas is compressed the greater becomes the resist ing force of said spring or gas, therefore the greater the power necessary to compress said spring or gas, and the old styled cams, such as are used on stamp-mills and rock-drills, take the spring nearest to the center of the cam, and as the cam is revolved the leverage power decreases, for the work to be done gets farther away from the center and at the same time the resisting force of the spring grows stronger. This results in a loss of one-half the power; but in the present instance the order of taking and releasing the load is simply reversed-{that is, the cam takes the spring when it is easiest to compress at its greatest length of leverage, that being at the point or too of the cam, and as the'cam is revolved the load is drawn toward the center. Therefore as the resisting force of the spring grows stronger the leverage power of the cam also grows stronger. By this order of manipulation no power is lost save friction, and, furthermore, the spring being released near the center of the cam there is very little jar to the machine or operator.

It is further my object to overcome the objection mentioned as incident to the old-style cams and at the same time so construct the body of the cam that it shall be free from all projections-such as springs, studs, or the likewhich are liable to be easily damaged or otherwise injured.

To the accomplishment of the above-re cited ends my invention consists in the peculiar construction, combination, and arrangement of parts described in this specification, delineatedin the accompanying drawings, and set forth in the appended claim.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar characters of reference indicate corresponding parts in all the figures.

Figure 1 is a perspective view of a cam embodying my improvements. Fig. 2 is 2. diagrammatic'view of my improvements, showing the cam in the act of commencing the compression of the spring at a point farthest from the center of the cam; and Fig. 3 is also a diagrammatic view showing the spring compressed at a point nearest the center or at the shortest point of leverage. It is also shown in a position for being released.

Referring now to the accompanying drawings, 1 designates the main body portion of the cam, which may be composed of any suitable or desired material, and in the present instance is shown ot preferably disk-like or circular conformationand is provided with a bore 2 for the reception of the shaft.

The face of the disk, which is shown at 3, is form ed with a groove or cut-away portion approximately the shape of a semiheartshaped cam. This groove may be of any desired depth to serve particular purposes, it being in the present instance equal in dimen- 3, is taken at the toe or point 4 of the cam which is farthestfrom the cam-shaft or center of the disk, and as the cam is revolving in the direction shown by the arrow the spring is compressed by the heel or swell portion of the cam-wheel, and as the cam makes a complete revolution it reaches a point nearest to the center of the cam, as shown in Fig. 3, and

as the cam continues its revolution it is released from the shoulder 5 thereof down to the farthest point or toe of the cam and is again carried up, as hereinbefore described, the operation being repeated.

While I have given a specific description of the shape of the construction of my improvement, it is of course to be understood that certain changes may be made in details without departing from the spirit of the invention-t-hat is to say, the cam might be of other shape than circular and the size of the formation of the cam-groove might also be varied at will, the principal object being to form a cam having a groove so constructed that the compression of the spring shall commence at the point farthest from the center or at the greatest point of leverage and shall be released at a point nearestthe center or at the shortest point of leverage.

Having thus described my invention, I claim as new and desire to secure by Letters Patent A cam comprising agrooved circular disk, formed with an acute shoulder near the center thereof, and a toe portion nearthe periphery thereof, said cam being adapted to compress a spring, such compression beginning at a point farthest from the center of the same, the spring being released at the shoulder por tion of said cam after a complete revolution of the latter, substantially as set forth.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

VVILLIAMII. DAILY.

Witnesses:

C. V. DONOVAN, A. L. MORAN. 

